Control and Status Protocol

1. An apparatus comprising: a host unit comprising a data device including a processor; and a wireless communication unit removably coupled to the host unit and including a transceiver, wherein the host unit and the wireless communication unit are configured to use a host interface protocol in communicating between the host unit and the wireless communication unit over a first interface, the host interface protocol defining a message header with a length field and message id field, the message id field allowing multiplexing between data stream transfers and status transfers for information sent between the host unit and wireless communication unit and wherein the host unit and the wireless communication unit are further configured to use a control and status protocol for control and status message transfers over the first interface between the host and the wireless communication unit, control and status messages being wrapped within host interface protocol messages, the wireless communication unit further configured to transmit data over a wireless network using a second interface.

2. The apparatus of claim 1 wherein transmissions between the host unit and the wireless communication unit include a data-link protocol.

3. The apparatus of claim 1 wherein the message ID field of the host interface protocol distinguishes between requests, responses, and indications.

4. The apparatus of claim 1 wherein the wireless communication unit is configured as a slave to the host unit.

5. The apparatus of claim 1 wherein the host unit is configured to produce request messages to send toward the wireless communication unit, and the wireless communication unit is configured to produce response messages in response to the requests.

6. The apparatus of claim 1 wherein a control message with a corresponding host interface protocol header message ID can be received within a buffer interspersed with messages for the data transmission to allow for multiplexing.

7. The apparatus of claim 1 wherein the wireless communication unit is configured as a modem unit.

8. An apparatus comprising: a host unit comprising a data device; and a wireless communication unit removably coupled to the host unit, the host unit and the wireless communication unit configured to use a host interface protocol for communications between the host unit and the wireless communication unit over a first interface, the host interface protocol defining a message header with a length field and message id field, the message id field allowing multiplexing between data stream transfers and control and status transfers for information sent into buffers of the host and wireless communication unit, the host unit and the wireless communication unit further configured to use a control and status protocol for control and status message transfers over the first interface between the host unit and the wireless communication unit, control and status messages being wrapped within host interface protocol messages, the wireless communication unit further configured to transmit data over a wireless network using a second interface.

9. The apparatus of claim 8 wherein the host unit and the wireless communication unit are further configured to use data link protocols.

10. The apparatus of claim 8 wherein the host interface protocol allows additional protocols besides the control and status protocol to be wrapped within the host interface protocol messages.

11. The apparatus of claim 8 wherein the host interface protocol message id fields can be used to indicate whether the messages are requests, responses or indications.

12. The apparatus of claim 8 wherein the data stream transfers are a type of indication.

13. The apparatus of claim 8 wherein the control message with the corresponding host interface protocol message ID can be received interspersed with messages for data transmission to allow for multiplexing.

14. The apparatus of claim 8 wherein the wireless communication unit is configured as a modem unit.

15. A computer implemented method comprising: at a wireless communication unit removably coupled to a host unit, receiving a control message from the host unit over a first interface, the host unit comprising a data device coupled to the wireless communication unit, the control message conforming to a host interface protocol by having a message header with a length field and a message identification field; and multiplexing the control message among one or more data transfers, the data transfers conforming to the host interface protocol by having a message header with a length field and a message identification field, the multiplexing accomplished using the message identification fields of the control message and the data transfers, the wireless communication unit further configured to transmit data over a wireless network using a second interface.

16. The method of claim 15 , further comprising: sending a response control message toward the host unit, the response control message corresponding to the control message but having a different value in the message identification field.

17. The method of claim 15 , wherein the control message is a request message and the message identification field identifies it as a request message.

18. The method of claim 17 , wherein a request message asks the wireless communication unit to perform an operation and/or return a value.

19. The method of claim 18 , wherein a response control message corresponding to the request message must be received by the host unit before the host unit generates another request message of the same type.

20. The method of claim 15 , wherein the control message is an indication message and the message identification field identifies it as an indication message.

21. The method of claim 20 , wherein a control message sends unsolicited data without the need for a response.

22. An apparatus comprising: means for, at a wireless communication unit removably coupled to a host unit, receiving a control message from the host unit over a first interface, the host unit comprising a data device coupled to the wireless communication unit, the control message conforming to a host interface protocol by having a message header with a length field and a message identification field; and means for multiplexing the control message among one or more data transfers, the data transfers conforming to the host interface protocol by having a message header with a length field and a message identification field, the multiplexing accomplished using the message identification fields of the control message and the data transfers, the wireless communication unit further configured to transmit data over a wireless network using a second interface.

23. The apparatus of claim 22 , further comprising: means for sending a response control message toward the host unit, the response control message corresponding to the control message but having a different value in the message identification field.

24. The apparatus of claim 22 , wherein the control message is a request message and the message identification field identifies it as a request message.

25. The apparatus of claim 24 , wherein a request message asks the wireless communication unit to perform an operation and/or return a value.

26. The apparatus of claim 25 , wherein a response control message corresponding to the request message must be received by the host unit before the host unit generates another request message of the same type.

27. The apparatus of claim 22 , wherein the control message is an indication message and the message identification field identifies it as an indication message.

28. The apparatus of claim 27 , wherein a control message sends unsolicited data without the need for a response.